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You searched for: Author marra Remove constraint Author: marra Subject term agricultural land Remove constraint Subject term: agricultural land Text availability Citation in PubAg Remove constraint Text availability: Citation in PubAg
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1. Remote measuring of the depth of wheel ruts in forest terrain using a drone

Author:
Elena Marra,   et al.   ; Rasmus Wictorsson; Jonas Bohlin; Enrico Marchi; Tomas Nordfjell;     Show all 5 Authors
Source:
International journal of forest engineering 2021 v.32 no.3 pp. 224-234
ISSN:
1913-2220
Subject:
agricultural land; altitude; compliance; flight; forest certification; forests; inventories; landscapes; models; photogrammetry; surveys
Abstract:
... Even at a well-managed harvesting site, vehicle trafficking occurs on at least 12% of the area and might cause ruts and compaction. The use of drones for inventory and mapping in forestry is still a new method. The purpose of this study was to develop a method for measuring the size and depth of wheel ruts caused by forest machines in harvested areas, using drones and Structure from Motion photogr ...
DOI:
10.1080/14942119.2021.1916228

2. The economic potential of fruit trees as shade in blue mountain coffee agroecosystems of the Yallahs River watershed, Jamaica W.I.

Author:
Peter Marra,   et al.   ; Herlitz Davis; Robert Rice; Larry Rockwood; Thomas Wood;     Show all 5 Authors
Source:
Agroforestry systems 2019 v.93 no.2 pp. 581-589
ISSN:
0167-4366
Subject:
Blighia sapida; Citrus; Mangifera indica; Musa; Persea americana; Syzygium samarangense; agricultural land; agroecosystems; agroforestry; altitude; ecosystem services; farm income; farmers; farms; fruit trees; fruits; grapefruits; habitats; livelihood; market access; marketing; rivers; roads; watersheds; Jamaica
Abstract:
... Studies in coffee agroecosystems often focus on the conservation and environmental benefits of this managed novel habitat, but rarely examine the socioeconomic benefit of the shade tree products themselves to coffee farmers. An examination of Blue Mountain coffee farmers along an elevation gradient within the Yallahs River watershed saw several tree species emerge as important within the agroecosy ...
DOI:
10.1007/s10457-017-0152-z

3. Switchgrass Yield on Reclaimed Surface Mines for Bioenergy Production

Author:
Michael Marra,   et al.   ; Travis Keene; Jeff Skousen; Thomas Griggs;     Show all 4 Authors
Source:
Journal of environmental quality 2013 v.42 no.3 pp. 696-703
ISSN:
0047-2425
Subject:
Panicum virgatum; agricultural land; bioenergy; biomass production; chemical composition; dry matter accumulation; economic feasibility; energy crops; feedstocks; forage quality; fuels; nonrenewable resources; perennial grasses; risk; sandstone; sludge; topsoil; warm season; West Virginia
Abstract:
... The high cost of transportation fuels and the environmental risks associated with acquiring and using nonrenewable energy sources have created a demand for developing renewable bioenergy crops. Switchgrass (Panicum virgatum L.), a warm-season perennial grass, is a promising feedstock due to its high biomass production under a wide range of growing conditions and its satisfactory forage quality and ...
DOI:
10.2134/jeq2012.0453

4. Landscape matrix and species traits mediate responses of Neotropical resident birds to forest fragmentation in Jamaica

Author:
Peter P. Marra,   et al.   ; Christina M. Kennedy; William F. Fagan; Maile C. Neel;     Show all 4 Authors
Source:
Ecological monographs 2010 v.80 no.4 pp. 651-669
ISSN:
0012-9615
Subject:
Neotropics; agricultural land; bauxite; canopy; community structure; diet; edge effects; foraging; forests; frugivores; granivores; habitat fragmentation; habitats; insectivores; land cover; land use; landscapes; limestone; mining; nectar feeding; neotropical birds; nests; omnivores; species richness; understory; Jamaica
Abstract:
... Land cover and land use surrounding fragmented habitat can greatly impact species persistence by altering resource availability, edge effects, or the movement of individuals throughout a landscape. Despite the potential importance of the landscape matrix, ecologists still have limited understanding of the relative effects of different types of land cover and land uses on species patterns and proce ...
DOI:
10.1890/09-0904.1

5. Coastal urbanization and the integrity of estuarine waterbird communities: Threshold responses and the importance of scale

Author:
Marra, Peter P.,   et al.   ; DeLuca, William V.; Studds, Colin E.; King, Ryan S.;     Show all 4 Authors
Source:
Biological conservation 2008 v.141 no.11 pp. 2669-2678
ISSN:
0006-3207
Subject:
environmental models; water birds; agricultural land; wildlife management; suburban areas; probability analysis; coasts; anthropogenic activities; urbanization; estuaries; prediction; forests; Chesapeake Bay
Abstract:
... Estuarine ecosystems are becoming increasingly altered by the concentration of human populations near the coastline, however a robust indicator of this change is lacking. We developed an index of waterbird community integrity (IWCI) and tested its sensitivity to anthropogenic activities within 28 watersheds and associated subestuaries of Chesapeake Bay, USA. The IWCI was used as a tool to gain ins ...
DOI:
10.1016/j.biocon.2008.07.023